Millimeter wave electric discharge device



' m 1957 G. DE VRIES ET L 9 v MILLIMETER WAVE ELECTRIC DISCHARGE DEVICE Filed Sept. 30 1952 INVENTOR GESINUS DIEMER GERRIT DE VRIES AGENT MILLIMETER WAVE ELECTRIC DISCHARGE DEVHCE Gen-it de Vries and Gesinus Diemer, Eindhoven, Nethen lands, assignors, by mesne assignments, to North American Philips Company, Inc., New York, N. Y., a corporation of Delaware Application September 30, 1952, Serial No. 312,362

Claims priority, application Netherlands November 9, 1951 2 Claims. (Cl. 315-4) The invention relates to a device for producing, amplifying or modulating millimeter waves comprising an electric discharge valve in which the resonance system is constituted by a plurality of approximately parallel wires of about a half-wave length which are stretched in juxtaposition on a frame so that their centre lines are spaced apart by a distance which is small compared with their length, and which interact with a cathode beam moving relatively to them.

Devices of the above-mentioned kind comprising parallel wires have been proposed before and to enable successive wires to oscillate in phase opposition they are made alternately longer and shorter than the average length. This has been described in a copending application, Serial No. 261,102, filed December 11, 1951.

The object of the invention is to provide other means to maintain the correct way of oscillation in the abovementioned devices.

According to the invention, in a millimeter wave device comprising an electric discharge tube the resonance system of which is constituted by a plurality of approximately parallel wires of about a half-wave length which are stretched in juxtaposition on a frame so that their centre lines are spaced apart by a distance which is small compared with their length, and which interact with a cathode beam moving relatively to them, the wires are alternately staggered relatively to their mutual parallel position in the opposite sense in the same plane so that the distances between the ends of the wires are alternately smaller and greater than the average distance, the ratio between the smaller distance and the greater one being at most 0.9 but not less than 0.7.

The manner indicated enables the voltage of the wires to oscillate in phase opposition and has the additional advantage that it is possible to use a single wire diameter and to place the Wires in position in a simple manner by winding them on the frame in succession left-hand and right hand instead of the structure shown by Gesinus Diemer in U. S. patent application, Serial No. 261,102 assigned to the assignee of the present invention.

2,797,354 Patented June 25, 1957 The invention will now be described with reference to the accompanying drawing, which shows a wound frame for an electric discharge tube to be used in a device according to the invention.

Referring to Figure 1 of the drawing the aperture 2 of a molybdenum sheet frame 1 is spanned by two groups of wires 3 and 4 respectively, the wires being mutually parallel in each group. The length l of the short side of the aperture is 4 mms. The great distance between two wires s is 0.32 mm. and the small distance s is 0.28 mm. The diameter of the wires is 0.1 mm. Each pair of adjacent wires of groups 3 and 4 thereby defines a trapezoidal space between the long sides of frame 1.

Figure 2 represents an electrode system for a discharge tube for use in a device according to the invention.

In the drawing the numerals 1 to 4 represent the same parts as in Figure l. 5 is an indirectly heated cathode. 6 is a focussing electrode and 7 a collecting anode, all located in an evacuated envelope 8. An electron beam is passed with the aid of electrodes 5, 6 and 7 along the frame 1 on which wires 3 and 4 are wound. The Wires 3 and 4 oscillate in phase opposition with voltage nodes at their ends. Any convenient means, such as a pick-up loop 9 connected to output terminals 10 and 11, may be used to extract electro-magnetic energy from the oscillating wires 3 and 4.

What we claim is:

l. A device adapted for extremely-high frequency operation, comprising a resonator including a planar conductive frame and a plurality of taut wires disposed in spaced relation on and secured to said frame, each of said wires having a length substantially equal to one-half of a wavelength of the operating frequency of the device, the spacing between adjacent wires being small relative to the length thereof, alternate wires being parallel to one another and adjacent wires being spaced apart a distance smaller at one side of the frame than at the other side whereby adjacent pairs of wires define similarly disposed trapezoidal spaces, the ratio between the smaller distance at one side of the frame and the larger distance at the other side being in the range between 0.7 and 0.9, and means for projecting an electron beam past said resonator in a direction parallel to said frame and substantially normal to said Wires to cause successive wires to oscillate in phase opposition.

2. A device as claimed in claim 1 in which the frame is constituted of molybdenum.

References Cited in the file of this patent UNITED STATES PATENTS 2,064,469 Haeil Dec. 15, 1936 2,439,401 Smith Apr. 13, 1948 2,584,308 Tiley Feb. 5, 1952 2,697,799 Svensson Dec. 21, 1954 

